This invention relates to receivers. In particular the invention relates to receivers for radio telephone systems which operate in a Time Division Multiple Access (TDMA) system.
With the impending adoption of the GSM (Groupe Speciale Mobile) system for a Pan-European Mobile Telephone System [see for example Electronics and Communication Engineering Journal Jan/Feb. 1989 vol. 1 no. 1 pp 7 to 13, "Pan-European cellular radio", D. M. Balston], a number of difficult technical problems have to be overcome for satisfactory implementation of the system.
In the GSM system, data to be transmitted is modulated on to a 900 MHz carrier signal by a Gaussian minimum shift keying technique (GMSK). Frequency channels are provided at a spacing of 200 KHz and data is transmitted on each channel at a total rate of 270.833 kbits.sup.-1.